- Haskell-Cafe - Haskell.org

Re: [Haskell-cafe] Ideas
by Andrew Coppin 27 Aug '07

27 Aug '07

Neil Mitchell wrote: > HI > > >>> Flippi (google: Haskell Flippi) >>> >> ...and yet haskell.org uses WikiMedia? (Which is written in something >> bizzare like Perl...) >> > > Yes, but WikiMedia is a result of years of work, Flippi is a lot less. > Wikipedia uses WikiMedia - its a tried and proven solution. > Well, I guess... I just thought, you know, the Tcl wiki is written in Tcl, why isn't the Haskell wiki written in Haskell? Hey, aren't we trying to tell people is a *useful* language that people should learn and use? ;-) >>>> - A "graphical programming tool". (You add boxes and put in lines, it >>>> constructs a "program" that you can run.) >>>> >> Have you ever played with KLogic? You draw boxes and lines, and it makes >> some logic. (As in the digital electronics sense of "logic".) >> >> I have some (very expensive) software called Reaktor. You draw boxes and >> lines, it does DSP algorithms. You build synthesizers and effects boxes >> with it. >> > > That sounds exactly like PureData - you can also do graphics as well > with PureData, the demo I saw was very cool. Of course, PureData is > written in C with Haskell as an extension language. > Oh. Ah well.. > The last two ideas you mentioned require a graphical user interface, > which is an area of Haskell which is comparatively weak, compared to > the rest of Haskell. > Yeah, I noticed. Though actually Gtk2hs isn't too bad. (There's a few corners that require bit-flipping and other low-level strangeness...)

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Help understanding a partial application
by Levi Stephen 27 Aug '07

27 Aug '07

Hi, I was browsing through the source code for Data.Foldable and having trouble comprehending it (which was kind of the point of browsing the code, so I could learn something ;) ) I'm looking at foldl foldl :: (c -> d -> c) -> c -> t d -> c foldl f z t = appEndo (getDual (foldMap (Dual . Endo . flip f) t)) z But, I haven't got very far. I'm still trying to follow: Endo . flip f f is of type c->d->c, so this makes flip f of type d->c->c. I think the Endo constructor is of type (a->a)->Endo a I think a is binding to a function type here, but can not work out what. (From memory) ghci reports > :t Endo . flip (+) Num a => a -> Endo a So, this looks like a partial application of the constructor? But, this still isn't helping me understand. Any thoughts or pointers that might help me comprehend what's happening? Thanks, Levi lstephen.wordpress.com

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Style
by Arie Groeneveld 27 Aug '07

27 Aug '07

Hi, I defined several functions for calculating the number of trailing zero's of n! tm = sum . takeWhile(>0) . iterate f . f where f = flip div 5 tm1 n = sum . takeWhile(>0) . map (div n . (5^)) $ [1..] tm2 n = sum . takeWhile(>0) . map (div n) $ iterate ((*)5) 5 tm3 = sum . takeWhile(>0) . flip map (iterate ((*)5) 5) . div Questions: Which one is the most elegant one generally speaking? Which one is most natural in Haskell? Is there more 'beauty' to possible? My personal choice is 'tm'. I like 'tm3' (a revised version of tm2) in terms of pointlessness and not having a 'where', but I think it's a bit contrived because of the 'flip'. Comments? Thanks @@i

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Re: [Haskell-cafe] Norvig's Sudoku Solver in Haskell
by Yitzchak Gale 27 Aug '07

27 Aug '07

I wrote: >> Perhaps you would gain something if you used Data.Map.! >> instead of your "lookup". Manu wrote: > I'm not sure I understand, do you mean I should have use a strict Map > constructor ? > like : Map !key !value ? No, there is an operator in Data.Map called "!". > how can it replace the lookup function ? Use > import qualified Data.Map as M > import Data.Map (!) Then, instead of "lookup k m" use "m ! k". >> Other than that, I'm not >> sure why your code runs slower than mine. Malte Milatz wrote: MM> The use of "length" here is not an actual MM> performance problem... Maybe not there, but I think Malte's suggestion might actually improve performance if you do the same thing a few lines further down, where you wrote: > case length dPlaces of By using Malte's idea there instead of length, you might allow some calculations inside dPlaces to be lazily skipped. Regards, Yitz

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arrows-.02 fails when rebuilding ghc 6.6.1
by Luc TAESCH 27 Aug '07

27 Aug '07

I try download and build 6.6.1 ( as ubntu has just 6.6 on package) and most went ok ( compiler and most libs) but arrows i tried and download arrow 0.2 from hackage but no more success any ideas ? ( knowing 6.6 is also on the machine if that matters) luc@haserv:~/src/arrows-0.2$ runghc Setup.hs build Preprocessing library arrows-0.2... Building arrows-0.2... [ 1 of 13] Compiling Data.Stream ( Data/Stream.hs, dist/build/Data/Stream.o ) [ 2 of 13] Compiling Control.Arrow.Transformer ( Control/Arrow/Transformer.hs, dist/build/Control/Arrow/Transformer.o ) [ 3 of 13] Compiling Control.Arrow.Operations ( Control/Arrow/Operations.hs, dist/build/Control/Arrow/Operations.o ) [ 4 of 13] Compiling Control.Arrow.Transformer.CoState ( Control/Arrow/Transformer/CoState.hs, dist/build/Control/Arrow/Transformer/CoState.o ) [ 5 of 13] Compiling Control.Arrow.Internals ( Control/Arrow/Internals.hs, dist/build/Control/Arrow/Internals.o ) [ 6 of 13] Compiling Control.Arrow.Transformer.Automaton ( Control/Arrow/Transformer/Automaton.hs, dist/build/Control/Arrow/Transformer/Automaton.o ) Control/Arrow/Transformer/Automaton.hs:98:0: Illegal instance declaration for `ArrowWriter w (Automaton a)' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowWriter w (Automaton a)' Control/Arrow/Transformer/Automaton.hs:104:0: Illegal instance declaration for `ArrowError r (Automaton a)' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowError r (Automaton a)' Control/Arrow/Transformer/Automaton.hs:115:0: Illegal instance declaration for `ArrowReader r (Automaton a)' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowReader r (Automaton a)' Control/Arrow/Transformer/Automaton.hs:120:0: Illegal instance declaration for `ArrowState s (Automaton a)' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowState s (Automaton a)' Control/Arrow/Transformer/Automaton.hs:126:0: Illegal instance declaration for `ArrowAddWriter w (Automaton a) (Automaton a')' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowAddWriter w (Automaton a) (Automaton a')' I discovered recently that my ubuntu package were providing only 6.6 and the latest cabal needs 6.6.1. when rebuilding this one from the tar ( not the head on darcs) most went ok but the arrows lib. I also tried to get it from hackage, but idem: ( I also have 6.6 on the machaine dos it matters ?) here is the build from hacakge with runghc : luc@haserv:~/src/arrows-0.2$ runghc Setup.hs build Preprocessing library arrows-0.2... Building arrows-0.2... [ 1 of 13] Compiling Data.Stream ( Data/Stream.hs, dist/build/Data/Stream.o ) [ 2 of 13] Compiling Control.Arrow.Transformer ( Control/Arrow/Transformer.hs, dist/build/Control/Arrow/Transformer.o ) [ 3 of 13] Compiling Control.Arrow.Operations ( Control/Arrow/Operations.hs, dist/build/Control/Arrow/Operations.o ) [ 4 of 13] Compiling Control.Arrow.Transformer.CoState ( Control/Arrow/Transformer/CoState.hs, dist/build/Control/Arrow/Transformer/CoState.o ) [ 5 of 13] Compiling Control.Arrow.Internals ( Control/Arrow/Internals.hs, dist/build/Control/Arrow/Internals.o ) [ 6 of 13] Compiling Control.Arrow.Transformer.Automaton ( Control/Arrow/Transformer/Automaton.hs, dist/build/Control/Arrow/Transformer/Automaton.o ) Control/Arrow/Transformer/Automaton.hs:98:0: Illegal instance declaration for `ArrowWriter w (Automaton a)' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowWriter w (Automaton a)' Control/Arrow/Transformer/Automaton.hs:104:0: Illegal instance declaration for `ArrowError r (Automaton a)' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowError r (Automaton a)' Control/Arrow/Transformer/Automaton.hs:115:0: Illegal instance declaration for `ArrowReader r (Automaton a)' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowReader r (Automaton a)' Control/Arrow/Transformer/Automaton.hs:120:0: Illegal instance declaration for `ArrowState s (Automaton a)' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowState s (Automaton a)' Control/Arrow/Transformer/Automaton.hs:126:0: Illegal instance declaration for `ArrowAddWriter w (Automaton a) (Automaton a')' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowAddWriter w (Automaton a) (Automaton a')' Control/Arrow/Transformer/Automaton.hs:135:0: Illegal instance declaration for `ArrowAddReader r (Automaton a) (Automaton a')' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowAddReader r (Automaton a) (Automaton a')' Control/Arrow/Transformer/Automaton.hs:144:0: Illegal instance declaration for `ArrowAddState r (Automaton a) (Automaton a')' (the Coverage Condition fails for one of the functional dependencies; Use -fallow-undecidable-instances to permit this) In the instance declaration for `ArrowAddState r (Automaton a) (Automaton a')' luc@haserv:~/src/arrows-0.2$ ------------------------------------------------------- here is a make from the build in the libraries tree under ghc 6.6.1 luc@haserv:~/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows$ make gcc -E -undef -traditional -P \ -DIMPORT_DIR='"/home/luc/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows"' \ -DLIB_DIR='"/home/luc/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows"' \ -DINCLUDE_DIR='"/home/luc/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows/include"' \ -DDATA_DIR='"/home/luc/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows"' \ -DHTML_DIR='"/home/luc/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows/html"' \ -DHADDOCK_IFACE='"/home/luc/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows/html/arrows.haddock"' \ -DFPTOOLS_TOP_ABS='"/home/luc/Desktop/ghc-6.6.1-src/ghc-6.6.1"' \ -x c -I../../includes -Iinclude -DPACKAGE=arrows -DVERSION=0.2.1 -DPKG_LIBDIR='"/usr/local/lib/ghc-6.6.1"' -DPKG_DATADIR='"/usr/local/share/ghc-6.6.1"' package.conf.in | \ grep -v '^#pragma GCC' | \ sed -e 's/""//g' -e 's/:[ ]*,/: /g' >package.conf.inplace gcc -E -undef -traditional -P -DINSTALLING \ -DIMPORT_DIR='"/usr/local/lib/ghc-6.6.1/imports"' \ -DLIB_DIR='"/usr/local/lib/ghc-6.6.1"' \ -DINCLUDE_DIR='"/usr/local/lib/ghc-6.6.1/include"' \ -DDATA_DIR='"/usr/local/share/ghc-6.6.1"' \ -DHTML_DIR='"/usr/local/share/ghc-6.6.1/html/libraries/arrows"' \ -DHADDOCK_IFACE='"/usr/local/share/ghc-6.6.1/html/libraries/arrows/arrows.haddock"' \ -x c -I../../includes -Iinclude -DPACKAGE=arrows -DVERSION=0.2.1 -DPKG_LIBDIR='"/usr/local/lib/ghc-6.6.1"' -DPKG_DATADIR='"/usr/local/share/ghc-6.6.1"' package.conf.in | \ grep -v '^#pragma GCC' | \ sed -e 's/""//g' -e 's/:[ ]*,/: /g' >package.conf.installed ../../utils/ghc-pkg/ghc-pkg-inplace update - --force-files <package.conf.inplace Reading package info from stdin ... done. /home/luc/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows/include doesn't exist or isn't a directory (ignoring) cannot find libHSarrows.a on library path (ignoring) Saving old package config file... done. Writing new package config file... done. ../../utils/ghc-pkg/ghc-pkg-inplace update - -f ../../driver/package.conf --force-files <package.conf.installed Reading package info from stdin ... done. cannot find libHSarrows.a on library path (ignoring) Saving old package config file... done. Writing new package config file... done. ../../compiler/ghc-inplace -H16m -O -fallow-undecidable-instances -package-name arrows-0.2.1 -O -Rghc-timing -fgenerics -package base -fgenerics -split-objs -c Control/Arrow/Internals.hs -o Control/Arrow/Internals.o -ohi Control/Arrow/Internals.hi Control/Arrow/Internals.hs:29:0: Failed to load interface for `Control.Arrow.Operations': Use -v to see a list of the files searched for. <<ghc: 24450740 bytes, 4 GCs, 136484/136484 avg/max bytes residency (1 samples), 16M in use, 0.00 INIT (0.00 elapsed), 0.16 MUT (0.51 elapsed), 0.07 GC (0.20 elapsed) :ghc>> make: *** [Control/Arrow/Internals.o] Error 1 luc@haserv:~/Desktop/ghc-6.6.1-src/ghc-6.6.1/libraries/arrows$

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Re: [Haskell-cafe] Norvig's Sudoku Solver in Haskell
by manu 27 Aug '07

27 Aug '07

> From: Malte Milatz <malte(a)gmx-topmail.de> > Subject: Re: [Haskell-cafe] Norvig's Sudoku Solver in Haskell > > Your program was wrapped by your mail client, so you may want to > hpaste > your program for easier digestion. > here it is : http://hpaste.org/2452 > > Your profiling output suggests that much time is consumed by the > lookup > function. Since you're using (fromJust . lookup) everywhere anyway, a > data structure not envolving the Maybe type is probably a more succint > choice. And why bother with characters and strings? > no rationale except that's what the original Python script did use >> newV2 <- case length newCell of >> 0 -> Nothing >> 1 -> do let peersOfS = [ s' | s' <- lookup s peers ] >> res <- foldM eliminate newV (zip peersOfS >> (cycle newCell)) >> return res >> _ -> return newV > > The use of “length” here is not an actual performance problem, but > unnecessary. Simply write: case newCell of [] -> ... > [_] -> ... > _ -> ... > > The same is valid for your other use of length. > > Malte I see, thanks ! E.D

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Norvig's Sudoku Solver in Haskell
by manu 27 Aug '07

27 Aug '07

Hello, After reading Peter Norvig's take on writing a Sudoku solver (http:// norvig.com/sudoku.html) I decided that I would port his program to Haskell, without changing the algorithm, that'll make a nice exercise I thought and should be fairly easy... Boy, was I wrong ! Anyway, I eventually managed to tiptoe around for loops, mutable state, etc... However, when I run my program against the test data provided (http:// norvig.com/top95.txt) I find it takes around 1m20 s to complete (compiled with -fvia-C and - O2, on a MacBook Pro 2.33GHz Intel Core 2 Duo). That's roughly 8 times longer than Norvig's Python script. That's not what I expected ! My program is also longer than the Python version. Being a beginner, I am convinced my implementation is super naive and non idiomatic. A seasonned Haskeller would do much shorter and much faster. I don't know how to improve it though ! Should I introduce more strictness ? replace lists with more efficient data structures (ByteStrings, Arrays) ? Here is my program, and part of the profiling (memory allocation looks huge !) I hope this post wasn't too long. Thanks for any advice ! Emmanuel. {- This is an attempt to implement in Haskell, Peter Norvig's sudoku solver : "Solving Every Sudoku Puzzle" (http://norvig.com/sudoku.html) In Norvig's program, methods which change a grid return either a new grid, either False (failure). Here I use Maybe, and return Just grid or Nothing in case of failure -} module Main where import Prelude hiding (lookup) import Data.List hiding (lookup) import qualified Data.Map as M import Control.Monad import Maybe import System.IO -------------------------------------------------- -- Types type Digit = Char type Square = String type Unit = [Square] -- We represent our grid as a Map type Grid = M.Map Square [Digit] -------------------------------------------------- -- Setting Up the Problem rows = "ABCDEFGHI" cols = "123456789" digits = "123456789" cross :: String -> String -> [String] cross rows cols = [ r:c:[] | r <- rows, c <- cols ] squares :: [Square] squares = cross rows cols -- ["A1","A2","A3",...] unitlist :: [Unit] unitlist = [ cross rows [c] | c <- cols ] ++ [ cross [r] cols | r <- rows ] ++ [ cross rs cs | rs <- ["ABC","DEF","GHI"], cs <- ["123","456","789"]] units :: M.Map Square [Unit] units = M.fromList [ (s, [ u | u <- unitlist, elem s u ]) | s <- squares ] peers :: M.Map Square [Square] peers = M.fromList [ (s, set [[ p | p <- e, p /= s ] | e <- lookup s units ]) | s <- squares ] where set = nub . concat -------------------------------------------------- -- Wrapper around M.lookup used in list comprehensions lookup :: (Ord a, Show a) => a -> M.Map a b -> b lookup k v = case M.lookup k v of Just x -> x Nothing -> error $ "Error : key " ++ show k ++ " not in map !" -- lookup k m = fromJust . M.lookup k m -------------------------------------------------- -- Parsing a grid into a Map parsegrid :: String -> Maybe Grid parsegrid g = do regularGrid g foldM assign allPossibilities (zip squares g) where allPossibilities :: Grid allPossibilities = M.fromList [ (s,digits) | s <- squares ] regularGrid :: String -> Maybe String regularGrid g = if all (\c -> (elem c "0.-123456789")) g then (Just g) else Nothing -------------------------------------------------- -- Propagating Constraints assign :: Grid -> (Square, Digit) -> Maybe Grid assign g (s,d) = if (elem d digits) then do -- check that we are assigning a digit and not a '.' let toDump = delete d (lookup s g) res <- foldM eliminate g (zip (repeat s) toDump) return res else return g eliminate :: Grid -> (Square, Digit) -> Maybe Grid eliminate g (s,d) = let cell = lookup s g in if not (elem d cell) then return g -- already eliminated -- else d is deleted from s' values else do let newCell = delete d cell newV = M.insert s newCell g -- newV2 <- case length newCell of -- contradiction : Nothing terminates the computation 0 -> Nothing -- if there is only one value (d2) left in square, remove it from peers 1 -> do let peersOfS = [ s' | s' <- lookup s peers ] res <- foldM eliminate newV (zip peersOfS (cycle newCell)) return res -- else : return the new grid _ -> return newV -- Now check the places where d appears in the units of s let dPlaces = [ s' | u <- lookup s units, s' <- u, elem d (lookup s' newV2) ] case length dPlaces of 0 -> Nothing -- d can only be in one place in unit; assign it there 1 -> assign newV2 (head dPlaces, d) _ -> return newV2 -------------------------------------------------- -- Search search :: Maybe Grid -> Maybe Grid search Nothing = Nothing search (Just g) = if all (\xs -> length xs == 1) [ lookup s g | s <- squares ] then (Just g) -- solved else do let (_,s) = minimum [ (length (lookup s g),s) | s <- squares, length (lookup s g) > 1 ] g' = g -- copie of g foldl' some Nothing [ search (assign g' (s,d)) | d <- lookup s g ] where some Nothing Nothing = Nothing some Nothing (Just g) = (Just g) some (Just g) _ = (Just g) -------------------------------------------------- -- Display solved grid printGrid :: Grid -> IO () printGrid = putStrLn . gridToString gridToString :: Grid -> String gridToString g = let l0= map snd (M.toList g) -- [("1537"),("4"),...] l1 = (map (\s -> " " ++ s ++ " ")) l0 -- [" 1 "," 2 ",...] l2 = (map concat . sublist 3) l1 -- [" 1 2 3 "," 4 5 6 ",...] l3 = (sublist 3) l2 -- [[" 1 2 3 "," 4 5 6 "," 7 8 9 "],...] l4 = (map (concat . intersperse "|")) l3 -- [" 1 2 3 | 4 5 6 | 7 8 9 ",...] l5 = (concat . intersperse [line] . sublist 3) l4 in unlines l5 where sublist n [] = [] sublist n xs = take n xs : sublist n (drop n xs) line = hyphens ++ "+" ++ hyphens ++ "+" ++ hyphens hyphens = take 9 (repeat '-') -------------------------------------------------- main :: IO () main = do h <- openFile "top95.txt" ReadMode grids <- hGetContents h let solved = mapMaybe (search . parsegrid) (lines grids) mapM_ printGrid solved hClose h ************************************************************************ *** Sun Aug 26 13:44 2007 Time and Allocation Profiling Report (Final) sudoku_norvig +RTS -p -hc -RTS total time = 49.40 secs (988 ticks @ 50 ms) total alloc = 6,935,777,308 bytes (excludes profiling overheads) COST CENTRE MODULE %time %alloc lookup Main 65.7 22.6 eliminate Main 32.4 70.3 search Main 1.8 6.3 individual inherited COST CENTRE MODULE no. entries % time %alloc %time %alloc MAIN MAIN 1 0 0.0 0.0 100.0 100.0 main Main 190 1 0.0 0.0 100.0 100.0 printGrid Main 214 95 0.0 0.0 0.0 0.1 gridToString Main 215 665 0.0 0.1 0.0 0.1 search Main 208 427143 1.8 6.3 99.4 99.2 assign Main 210 468866 0.1 0.6 90.4 90.3 eliminate Main 212 30626903 32.2 69.8 89.9 89.6 lookup Main 213 172203504 57.7 19.9 57.7 19.9 lookup Main 211 468866 0.4 0.1 0.4 0.1 lookup Main 209 22447632 7.2 2.6 7.2 2.6 parsegrid Main 192 95 0.0 0.0 0.6 0.7 assign Main 198 7695 0.0 0.0 0.6 0.7 eliminate Main 201 51054 0.2 0.5 0.6 0.7 lookup Main 202 1239860 0.4 0.1 0.4 0.1 lookup Main 200 1953 0.0 0.0 0.0 0.0 ... (more innocuous stuff)

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Re: [Haskell-cafe] Re: Parsec is being weird at me
by Andrew Coppin 27 Aug '07

27 Aug '07

Chris Casinghino wrote: > On 8/25/07, Andrew Coppin <andrewcoppin(a)btinternet.com> wrote: > >> >> I thought the whole *purpose* of the endBy combinator was to keep >> applying one parser until the other one succeeds? >> > > > I don't think this is a lookahead problem, but rather just a > misreading of the spec of endBy. Here it is: > > (endBy p sep) parses zero or more occurrences of p, seperated and > ended by sep. Returns a list of values returned by p. > > The key text is "seperated and ended by sep". Not just ended by. > ...so then what does sepEndBy do?

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nested datatypes
by Thomas Girod 27 Aug '07

27 Aug '07

Hi there. recently I was trying to represent complex data by defining several datatypes and nesting them, such as data Foo = Foo { foo :: Bar } deriving (Eq,Show) data Bar = Bar { bar :: Int } deriving (Eq,Show) To change only a part of the data, syntactic sugar is quite convenient. But it seems to be quite painful with nested datatypes. b = Bar 10 f = Foo b foobar :: Int -> Foo -> Foo foobar i f = let nb = (foo f){bar = i} in f{foo = nb} So, my question is : is there a nifty way to modify data within a nested datatype, similar to the f{foo = bar} style ? If not, anyone is using some kind of workaround for this ?

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Hugs on Zaurus
by Ulrich Vollert 27 Aug '07

27 Aug '07

> Haskell could run on such a platform". Ofcourse this is completly > other way around in terms of power and memory. :) > > But anyway, did anyone do it? I compiled Hugs for my Sharp Zaurus SL-C3200 (http://www.trisoft.de) which is a PDA with an ARM processor. (System: Lineo uLinux , CPU: Intel® XScale™ (PXA270, 416 MHz)) Hugs was compiled by gcc 2.95.3 and can be used in the console, additionally under a special X/Qt-Environment called pdaXqtrom (http://www.users.on.net/~hluc/myZaurus/) So, it is possible to use graphics on the Zaurus, too. I didnt dare to port ghc or Yhc - which would be great to use on the Zaurus, too. Regards, Ulrich

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